There are many efforts to use technology to provide aid—and in particular, navigational aid—to the blind or otherwise visually impaired. The technologies available today, including the global positioning system (GPS) and other global navigation satellite systems (GNSS) and powerful mobile computing platforms, have enabled a range of attempted solutions.
Unfortunately, many of the solutions offered today fall short of ideal. Some are based on a mobile platform such as a smart phone or tablet computer for which the human interface was designed entirely for sighted people. Although it is sometimes possible to purchase modules which can be plugged into these devices to add a Braille interface or to translate visual components into audible directives, this is less than ideal, as the platform itself, the hosting device, was still never intended to be used by someone who cannot see the display. The user interfaces on most devices, in fact, consist almost entirely of a touch screen, in which virtual controls can be displayed in any location and offer no raised edge or surface with can be felt by touch.
Another problem with existing solutions is that many are based on expensive or complex sensing systems, such as sonar, radar, or laser detection, which require setup, mounting, orientation, calibration, and adjustment not easily done by the blind. These systems must also be interfaced to a computer (such as the aforementioned mobile computing platform) that interprets the readings and controls the performance of the sensors. These sensing systems must be mounted to something that must be with the visually impaired person at all times. Some solutions mount the sensors on a walking stick (cane), and others mount them directly on the blind person themselves. These solutions can take the spontaneity out of a quick morning walk around the block, as you have to take time to put the system on, boot it up, and make sure it is working before you leave the house.
Commercial versions of GPS products for the visually impaired include examples such as the Sendero GPS system (Sendero Group, LLC, Roseville, Calif.), Trekker GPS Software (HumanWare Group, Drummondville, Quebec, Canada), StreetTalk GPS Software (Freedom Scientific, St. Petersburg, Fla.), and MobileGeo GPS System (Sendero Group, LLC, Roseville, Calif.), all of which run on a personal data assistant or mobile computing device. These solutions are based on handheld GPS solutions to help the visually-impaired navigate around the city. The systems have varying levels of sophistication and features, but generally provide audible navigation instructions to the user between points of interest or toward a destination to help them get where they are going in an unfamiliar location. These systems are helpful when traveling, but can be expensive and do not provide obstacle detection. They are simply glorified handheld GPS solutions, with software solutions tailored for the visually impaired, but dependent on mobile platforms designed for the fully sighted.
One variation on the GPS approach is a “haptic shoe,” a shoe which provides feedback in the form of a mild vibration to the wearer to indicate they should turn in one direction or the other. This solution, although clever and unobtrusive, relies on the same GPS-based computer systems as the previously described solutions to get the actual navigation data, and still has all of their inherent problems.
Other solutions exist or are in development. A research group originally based at the University of Southern California working with Gerard Medioni, a professor in the Institute for Robotics and Intelligent Systems at USC Viterbi, is developing a system which uses head-mounted or body-mounted cameras and special software to build maps of the environment through which a person is walking and identify a safe path through that environment. The solution then alerts the user to obstacles, and to the relative location of those obstacles, by vibrating different parts of a vest worn by the user to indicate the direction of the obstacle. This solution is dependent on the user wearing a lot of sensing and feedback equipment, including a tactile feedback vest, and requires that cameras be mounted on the user's head or other parts of the body. This solution would require time to set up, and is dependent on a lot of complex systems and sensors working together.
The Yissum Research Development Company, Hebrew University's technology transfer firm, has developed a product which adds sonar-like sensors to a walking cane to detect objects in the path where a visually-impaired person is traveling. This system would provide vibration or other feedback to the user to provide an “image” of the immediate environment around the user. This system relies on a complex sensor system, an unobstructed beam which must be pointed in the right direction in order to work, and a controlling computer system that will require setup. Other variations on this approach exist, in which sonar or other emitting sources are used to gauge distance to objects and provide feedback to a user.
What is needed in the art is a navigation aid for the visually impaired which has a simple user interface, designed specifically to be operated by touch and vocal commands, is not dependent on a complex computer system or a lengthy calibration or orientation, does not require the user to wear special clothing or equipment, and which is small, inexpensive, and available to all.